Portable lumbar traction device

ABSTRACT

A low-cost, light weight portable lumbar fraction device for home use by a patient including a support structure having a longitudinal axis and a carriage slidable along a portion of the support structure parallel to the longitudinal axis. The carriage includes a restraining mechanism adapted to releasably restrain a portion of a patient&#39;s body to the carriage. The pneumatic fraction force generating apparatus includes at least one pneumatic chamber and at least one air inlet. The pneumatic traction force generating apparatus is operatively coupled to both the carriage and the support structure to move the carriage relative to the support structure when the at least one pneumatic chamber is in a pressurized state. The pneumatic fraction force generating apparatus is adapted to maintain a generally static fraction force for a period in excess of 10 minutes when in the pressurized state without additional pressurized air being supplied. A hand pump operated by the patient is fluidly connected to the at least one pneumatic chamber for injecting pressurized air into the at least one pneumatic chamber. The hand pump is capable of injecting at least 138 kPa (20 psi) of pressure into the pneumatic chamber. A pressure relief mechanism operated by the patient is adapted to release pressure from the at least one pneumatic chamber.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 10/320,589 filed Dec. 16, 2002 now U.S. Pat. No. 6,899,690entitled Portable Traction Device, which is a continuation of of U.S.patent application Ser. No. 08/817,444, filed Oct. 22, 1997, now U.S.Pat. No. 6,506,174, which is a continuation of PCT/US95/14217 filed Oct.31, 1995, which claims priority to and is a continuation-in-part of U.S.patent application Ser. No. 08/334,189 filed Nov. 3, 1994 (abandoned).

FIELD OF THE INVENTION

The present invention is directed to a portable traction device poweredby a pneumatic cylinder.

BACKGROUND OF THE INVENTION

Traction is widely used to relieve pressure on inflamed or enlargednerves. While traction is applicable to any part of the body, cervicaland lumbar or spinal traction are the most common. When correctlyperformed, spinal traction can cause distraction or separation of thevertebral bodies, a combination of distraction and gliding of the facetjoints, tensing of the liganentous structures of the spinal segment,widening of the intervertebral foremen, straightening of spinalcurvature and stretching of the spinal musculature. Depending on theinjury being treated, the traction component of physical therapy mayrequire multiple sessions per week for a prolonged period of time.

Cervical traction requires a traction force up to approximately 222 N(50 lbs.). Lumbar traction typically requires force equal to half of thepatient's bodyweight, or about 333–667 N (75–150 lbs.). The equipmentnecessary for performing traction, however, has typically been expensiveand thus only available to a patient in a therapist's office.

Attempts to create a sufficiently low cost portable traction device forhome use have thus far produced unsatisfactory results. A number ofportable traction devices utilize pneumatic or hydraulic cylinders tocreate the traction force. Hydraulic cylinders have the disadvantage ofthe weight of the hydraulic fluid. Pneumatic cylinders with low pressureinputs typically can not maintain an adequate traction force for asufficient period of time to be effective in a traction device. In anattempt to overcome this deficiency, some of these devices utilize anautomatic pumping device triggered by a pressure sensing device tosupply additional compressed air so that a constant level of tractionforce is maintained. These pump and sensor configurations add cost,weight and complexity to the traction device.

The air input pumps used on some traction devices also exhibit a numberof shortcomings. For example, bulb-type air pumps produce relativelysmall input pressures. A small female patient can generate only about483 kPa (7 psi) of pressure using a bulb-type pump. Consequently, smallinput pressure devices require large diameter cylinders to generate thenecessary output traction forces. Larger diameter cylinders, when usedwith low pressure input devices, are more prone to leak, thereby furthercomplicating the problem of maintaining a constant traction force for aprolonged period of time.

Therefore, what is needed is a low cost, light weight portable tractiondevice utilizing a pneumatic cylinder which can maintain a tractionforce of an adequate magnitude for a prolonged period of time.

SUMMARY OF THE INVENTION

The present invention is directed to a portable traction device poweredby a pneumatic traction force generating apparatus. The presentinvention is also directed to a pneumatic traction force generatingapparatus suitable for use in traction devices.

In one embodiment, the low-cost, light weight portable lumbar tractiondevice for home use by a patient includes a support structure having alongitudinal axis and a carriage slidable along a portion of the supportstructure parallel to the longitudinal axis. The carriage includes arestraining mechanism adapted to releasably restrain a portion of apatient's body to the carriage. The pneumatic traction force generatingapparatus includes at least one pneumatic chamber and at least one airinlet. The pneumatic traction force generating apparatus is operativelycoupled to both the carriage and the support structure to move thecarriage relative to the support structure when the at least onepneumatic chamber is in a pressurized state. The pneumatic tractionforce generating apparatus is adapted to maintain a generally statictraction force for a period in excess of 10 minutes when in thepressurized state without additional pressurized air being supplied. Ahand pump operated by the patient is fluidly connected to the at leastone pneumatic chamber for injecting pressurized air into the at leastone pneumatic chamber. The hand pump is capable of injecting at least138 kPa (20 psi) of pressure into the pneumatic chamber. A pressurerelief mechanism operated by the patient is adapted to release pressurefrom the at least one pneumatic chamber.

In one embodiment, the restraining mechanism is a waist belt adapted toreleasably restrain a portion of the patient's lower body to thecarriage and a restraining belt adapted to restrain a portion of thepatient's upper body to the support structure. In another embodiment,the restraining mechanism is a pair of opposing, laterally adjustablehip gripping supports contoured and arranged to engage with the superioredge of the patient's pelvis as the carriage slides along the supportstructure.

In one embodiment, the carriage includes a support surface to receive aportion of the patient's lower body and a counter fraction restraint torestrain a portion of the patient's upper body to the support structure.The carriage slides in a direction away from the counter tractionrestraint when pressurized air is introduced into the at least onepneumatic chamber.

In one embodiment, the at least one pneumatic chamber is capable ofmaintaining a generally static traction force of greater than 111 N (25pounds) for a period, in excess of 10 minutes without additionalpressurized air being injected into the at least one pneumatic chamber.In another embodiment, the at least one pneumatic chamber is capable ofmaintaining a generally static traction force of greater than 200 N (45pounds) for a period in excess of 20 minutes without additionalpressurized air being injected into the at least one pneumatic chamber.In yet another embodiment, the at least one pneumatic chamber is capableof maintaining a generally static traction force of greater than 445 N(100 pounds) for a period in excess of 10 minutes without additionalpressurized air being injected into the at least one pneumatic chamber.In still another embodiment, the at least one pneumatic chamber iscapable of maintaining a generally static traction force of greater than890 N (200 pounds) for a period in excess of 20 minutes withoutadditional pressurized air being injected into the at least onepneumatic chamber.

The present traction device optionally includes a gauge indicatingtraction force and/or at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value. A pressure relief mechanism operated by the patientis preferably incorporated in the user operated hand pump.

The pneumatic traction force generating apparatus can optionally includeat least one pneumatic cylinder. In one embodiment, the at least onepneumatic cylinder optionally includes at least one pressure activatedseal in the pneumatic cylinder extending circumferentially around apiston. In this embodiment, the pressure activated seal is movablebetween a relaxed position and an extended position so the pressureactivated seal engages an internal surface on the pneumatic cylinderwhen the pneumatic cylinder is in the pressurized state.

In another embodiment, the low-cost, light weight portable lumbartraction device for home use by a patient includes an upper body supportplatform having an upper body support surface and a lower body supportplatform having a lower body support surface. The restraining mechanismis adapted to releasably restrain a portion of a patient's body to atleast one of the upper or lower body support platforms. At least onepneumatic traction force generating apparatus includes at least onepneumatic chamber and at least one air inlet. The traction forcegenerating apparatus is operatively coupled to at least one of the upperor lower body support platforms to displace at least one of the upperand lower body support platforms relative to the other along alongitudinal axis. The at least one pneumatic traction force generatingapparatus maintains a generally static traction force for a period inexcess of 10 minutes when in the pressurized state without additionalpressurized air being supplied. A hand pump operated by the patient isfluidly connected to the at least one pneumatic traction forcegenerating apparatus for injecting pressurized air into the at least onepneumatic traction force generating apparatus. The hand pump is capableof injecting at least 138 kPa (20 psi) of pressure into the at least onepneumatic traction force generating apparatus. A pressure reliefmechanism operated by the patient is adapted to release pressure fromthe at least one pneumatic chamber.

In one embodiment, the restraining mechanism includes a waist beltadapted to releasably restrain a portion of the patient's lower body tothe lower body support platform and a restraining belt adapted torestrain a portion of the patient's upper body to the upper body supportplatform. In another embodiment, the restraining mechanism includes apair of opposing, laterally adjustable hip gripping supports contouredand arranged to engage with a superior edge of the patient's pelvis asthe lower body support platform slides along the support structure. Inyet another embodiment, the restraining mechanism includes frictionbetween at least one of the body support surfaces and a portion of thepatient.

The present traction device optionally includes a gauge indicatingtraction force and/or at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value. A pressure relief mechanism operated by the patientis preferably incorporated in the user operated hand pump.

A hinge optionally connects the upper body support platform to the lowerbody support platform. The hinge optionally facilitates shipping andstorage of the portable lumbar traction device. In one embodiment, theupper and lower body support platforms are adapted to be positioned on afloor.

The pneumatic traction force generating apparatus can optionally includeat least one pneumatic cylinder. In one embodiment, the at least onepneumatic cylinder optionally includes at least one pressure activatedseal in the pneumatic cylinder extending circumferentially around apiston. In this embodiment, the pressure activated seal is movablebetween a relaxed position and an extended position so the pressureactivated seal engages an internal surface on the pneumatic cylinderwhen the pneumatic cylinder is in the pressurized state.

In another embodiment, the low-cost, light weight portable lumbartraction device for home use by a patient includes a support structurehaving a track and a carriage slidable along a portion of the track. Therestraining mechanism is adapted to releasably restrain a portion of apatient's body to the carriage. At least one pneumatic cylinder isoperatively coupled to the carriage and the support structure to movethe carriage along the track relative to the support structure when in apressurized state. The at least one pneumatic cylinder maintains agenerally static traction force during a treatment period when in thepressurized state without additional pressurized air being supplied. Ahand pump operated by the patient is fluidly connected to the at leastone pneumatic cylinder and adapted to inject pressurized air into the atleast one pneumatic cylinder. A pressure relief mechanism operated bythe patient is adapted to release pressure from the at least onepneumatic cylinder.

The present traction device optionally includes a gauge indicatingtraction force and/or at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value. A pressure relief mechanism operated by the patientis preferably incorporated in the user operated hand pump.

In one embodiment, the at least one pneumatic cylinder optionallyincludes at least one pressure activated seal in the pneumatic cylinderextending circumferentially around a piston. In this embodiment, thepressure activated seal is movable between a relaxed position and anextended position so the pressure activated seal engages an internalsurface on the pneumatic cylinder when the pneumatic cylinder is in thepressurized state.

In another embodiment, the present low-cost, light weight portablelumbar traction device for home use by a patient includes an upper bodysupport platform having an upper body support surface and a lower bodysupport platform having a lower body support surface. The restrainingmechanism is adapted to releasably restrain a portion of a patient'sbody to at least one of the upper or lower body support platforms. Atleast one pneumatic cylinder is adapted to displace at least one of theupper and lower body support platforms relative to the other along alongitudinal axis. The at least one pneumatic cylinder maintains agenerally static traction force during a treatment period when in thepressurized state without additional pressurized air being supplied. Ahand pump operated by the patient is fluidly connected to the at leastone pneumatic cylinder for injecting pressurized air into the at leastone pneumatic cylinder. The hand pump is capable of injecting at least138 kPa (20psi) of pressure into the at least one pneumatic cylinder. Apressure relief mechanism operated by the patient is adapted to releasepressure from the at least one pneumatic cylinder.

In one embodiment, the restraining mechanism includes a waist beltadapted to releasably restrain a portion of the patient's lower body tothe lower body support platform and a restraining belt adapted torestrain a portion of the patient's upper body to the upper body supportplatform. In another embodiment, the restraining mechanism includes apair of opposing, laterally adjustable hip gripping supports contouredand arranged to engage with a superior edge of the patient's pelvis asthe lower body support platform slides along the support structure. Inyet another embodiment, the restraining mechanism includes frictionbetween at least one of the body support surfaces and a portion of thepatient.

The present traction device optionally includes a gauge indicatingtraction force and/or at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value. A pressure relief mechanism operated by the patientis preferably incorporated in the user operated hand pump.

A hinge optionally connects the upper body support platform to the lowerbody support platform. The hinge optionally facilitates shipping andstorage of the portable lumbar traction device, in one embodiment, theupper and lower body support platforms are adapted to be positioned on afloor.

In one embodiment, the at least one pneumatic cylinder optionallyincludes at least one pressure activated seal in the pneumatic cylinderextending circumferentially around a piston. In this embodiment, thepressure activated seal is movable between a relaxed position and anextended position so the pressure activated seal engages an internalsurface on the pneumatic cylinder when the pneumatic cylinder in thepressurized state.

In another embodiment, the low-cost, light weight portable lumbartraction device for home use by a patient includes a support structurehaving a track and at least one carriage slidable along a portion of thetrack. The restraining mechanism is adapted to releasably restrain aportion of a patient's body to the carriage. The pneumatic tractionforce generating apparatus includes at least one pneumatic cylinderhaving a first end and a moveable piston at a second end. One of thepneumatic cylinder or the piston is attached to a support structure, andthe other is attached to the carriage. The at least one pneumaticcylinder is adapted to move the carriage along the track relative to thesupport structure when in a pressurized state. The pneumatic tractionforce generating apparatus maintains a generally static traction forceduring a treatment period when in the pressurized state withoutadditional pressurized air being supplied. A hand pump operated by thepatient is fluidly connected to the at least one pneumatic cylinder andadapted to inject pressurized air into the at least one pneumaticcylinder. A pressure relief mechanism operated by the patient is adaptedto release pressure from the at least one pneumatic cylinder.

A user operated pressure relief mechanism is preferably incorporated inthe user operated hand pump. In one embodiment, the carriage includes anupper body support platform having an upper body support surface and alower body support platform having a lower body support surface.

In one embodiment, the at least one pneumatic cylinder optionallyincludes at least one pressure activated seal in the pneumatic cylinderextending circumferentially around a piston. In this embodiment, thepressure activated seal is movable between a relaxed position and anextended position so the pressure activated seal engages an internalsurface on the pneumatic cylinder when the pneumatic cylinder is in thepressurized state.

In another embodiment, the low-cost, light weight portable tractiondevice for home use by a patient includes a support structure and acarriage generally slidable along a portion of the support structure.The carriage includes a restraining mechanism adapted to releasablyrestrain a portion of a patient's body to the carriage. At least onepneumatic traction force generating apparatus is provided that includesat least one pneumatic chamber and at least one air inlet. The tractionforce generating apparatus is operatively coupled to the carriage andthe support structure to move the carriage relative to the supportstructure when the at least one pneumatic traction force generatingapparatus is in a pressurized state. The at least one pneumatic tractionforce generating apparatus maintains a generally static traction forcefor a period in excess of 10 minutes when in the pressurized statewithout additional air being supplied. A hand pump operated by thepatient is fluidly connected to the at least one pneumatic tractionforce generating apparatus for injecting air into the at least onepneumatic traction force generating apparatus. A user operated pressurerelief mechanism operated by the patient is adapted to release pressurefrom the at least one pneumatic chamber.

In one embodiment, the restraining mechanism includes first and secondbelts. The first belt is adapted to releasably restrain a first portionof the patient's body to the carriage and the second belt is adapted torestrain a second portion of the patient's body to the supportstructure. In one embodiment, the first belt is adapted to releasablyrestrain a portion of the patient's lower body to the carriage and thesecond belt is adapted to restrain a portion of the patient's upper bodyto the support structure. in another embodiment, the first belt isadapted to releasably restrain a portion of the patient's upper body tothe carriage and the second belt is adapted to restrain a portion of thepatient's body to the support structure. In yet another embodiment, therestraining mechanism includes a pair of opposing, laterally adjustablegripping supports. The laterally adjustable gripping supports areoptionally contoured and arranged to engage with the superior edge ofthe patient's pelvis as the carriage slides along the support structure.

In one embodiment, the carriage includes a support surface to receive aportion of the patient's lower body and a counter traction restraint torestrain a portion of the patient's upper body to the support structure.The carriage slides in a direction away from the counter tractionrestraint when air is introduced into the at least one pneumatictraction force generating apparatus.

The present traction device optionally includes a gauge indicatingtraction force and/or at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value. A pressure relief mechanism operated by the patientis preferably incorporated in the user operated hand pump.

In one embodiment, the at least one pneumatic chamber includes at leastone pneumatic cylinder. In this embodiment, the pneumatic cylinderoptionally includes at least one pressure activated seal in thepneumatic cylinder extending circumferentially around a piston. In thisembodiment, the pressure activated seal is movable between a relaxedposition and an extended position so the pressure activated seal engagesan internal surface on the pneumatic cylinder when the pneumaticcylinder is in the pressurized state.

In another embodiment, the low-cost, light weight portable lumbartraction device for home use by a patient includes a support structurehaving a longitudinal axis and a carriage slidable along a portion ofthe support structure parallel to the longitudinal axis. The carriageincludes a restraining mechanism adapted to releasably restrain aportion of a patient's body to the carriage. At least one pneumatictraction force generating means is provided for moving the carriagerelative to the support structure when the at least one pneumatictraction force generating means is in a pressurized state. The at leastone a pneumatic traction force generating means maintains a generallystatic traction force for a period in excess of 10 minutes when in thepressurized state without additional pressurized air being supplied. Ahand pump operated by the patient is fluidly connected to the at leastone a pneumatic traction force generating means for injectingpressurized air into the at least one pneumatic traction forcegenerating means. The hand pump is capable of injecting at least 138 kPa(20 psi) of pressure into the pneumatic traction force generating means.A pressure relief mechanism operated by the patient is adapted torelease pressure from the at least one pneumatic traction forcegenerating means.

In another embodiment, the low-cost, light weight portable lumbartraction device for home use by a patient includes an upper body supportplatform having an upper body support surface and a lower body supportplatform having a lower body support surface. The restraining mechanismis adapted to releasably restrain a portion of a patient's body to atleast one of the upper or lower body support platforms. At least onepneumatic traction force generating means is provided for displacing atleast one of the upper and lower body support platforms relative to theother along a longitudinal axis. The at least one pneumatic tractionforce generating means maintains a generally static traction force for aperiod in excess of 10 minutes when in the pressurized state withoutadditional pressurized air being supplied. A hand pump operated by thepatient is fluidly connected to the at least one pneumatic tractionforce generating means for injecting pressurized air into the at leastone pneumatic traction force generating means. The hand pump is capableof injecting at least 138 kPa (20 psi) of pressure into the at least onepneumatic traction force generating means. A pressure relief mechanismoperated by the patient is adapted to release pressure from the at leastone pneumatic traction force generating means.

The present invention is also directed to the pneumatic traction forcegenerating apparatus and hand pump discussed above for use as thetraction force generating apparatus on a portable traction device.

The present invention is also directed to the pneumatic cylinder andhand pump discussed above for use as the traction force generatingapparatus on a portable traction device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a portable traction device;

FIG. 2 is a top view of the portable traction device of FIG. 1;

FIG. 3 is an end view of the portable traction device of FIG. 1illustrating a laterally adjustable neck support;

FIG. 4 is a side view of a patient utilizing the traction device of FIG.1;

FIG. 5 is a schematic illustration of an exemplary pneumatic cylinderfor use with a portable traction device;

FIG. 6 is a top view of an exemplary air pump;

FIG. 7 is a side view of the exemplary air pump of FIG. 6;

FIG. 8 illustrates an exemplary portable, lumbar traction device;

FIGS. 9 a–9 c illustrate a top, front and end view of an alternateportable lumbar traction device;

FIG. 10 illustrates a pneumatic cylinder configuration for use with aportable, lumbar traction device; and

FIG. 11 illustrates a hip gripping device for a portable, lumbartraction device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 and 2 illustrate an exemplary portable, cervical traction device20 in which a carriage 22 and slide portion 24 are allowed to movefreely on a track 26 along a direction “S” (see also FIG. 3). The slideportion 24 includes a slide bracket 28 which engages with a piston rod30 on a pneumatic cylinder 32 mounted underneath the track 26. A lateraladjustment mechanism 38, a head support pad 76, and a pair of V-shapedneck supports 50, 52 (see FIG. 3), are mounted to the carriage 22, whichwill be discussed in detail below. The pneumatic cylinder 32 is attachedto the track 26 by an angle bracket 34. An air line 40 is attached to anair inlet 42 at one end of cylinder 32 for providing pressurized air tothe cylinder 32. An alternate V-shaped neck support structure suitablefor use in the present invention is disclosed in U.S. Pat. No. Re.32,791 issued to Saunders on Nov. 29, 1988, which is hereby incorporatedby reference.

The angle bracket 34 also serves the purpose of retaining the track 26at an angle a relative to a support surface 36. A removable stabilizerbracket 35 may optionally be added to prevent the angle bracket 34 fromlifting off of the support surface 36 during use. A pad 37 preferably isplaced over the angle bracket 34 for the comfort of the user. It will beunderstood that the length of the angle bracket 34 may be adjustabledepending on the application of the portable traction device 20. Forexample, the angle bracket 34 may be of a telescoping constructions. Itwill also be understood that the slide portion 24 may engage with thetrack 26 in a variety of configurations, and that the present inventionis not limited to the specific embodiment disclosed herein. The track26, carriage 22, and slide portions 24 are preferably constructed of alightweight, low cost material, such as, for example, aluminum, steel,high density plastic, or a variety of composite materials.

FIG. 3 is an end view of the lateral adjustment mechanism 38 on thecarriage 22. Left and right neck supports 50, 52 form a V-shaped necksupport structure that generally follows the contour of the base of theuser's skull. The neck supports 50, 52 are attached to a pair ofcorresponding lateral slides 54, 56 on the carriage 22. The lateralslides 54, 56 are engaged with the threaded shaft 58 by a pair ofcoupler nuts 60, 62. The portion of the shaft 58 proximate coupler nut60 has left-hand threads and the portion proximate coupler nut 62 hasright-hand threads. The lateral position of the V-shaped neck supports50, 52 is adjusted by turning the left and right knobs 70, 72. The necksupports 50, 52 are ideally positioned around the patient's head so thatthey contact and follow the contour of the occipital bone at the base ofthe patient's skull, while the back of the patient's skull rests on thehead support pad.

FIG. 4 illustrates a patient 78 utilizing the portable traction device20 on a support surface 36. It will be understood that the presentportable traction device 20 may be used on a variety of supportsurfaces, such as for example, a floor, a table, or any other suitablesurface. It will also be understood that the support surface 36 does notnecessarily have to be horizontal and that it may be desirable to havean angled support surface for some types of traction. A support strap 77may optionally be used to restrain the patient's head to the headsupport pad 76 during traction.

FIG. 5 is a schematic illustration of a single-acting pneumatic cylinder32 for use with a present portable traction device. Piston 80 has adiameter “P” which is slightly smaller than the inside diameter “C” ofthe cylinder 32 so that a small gap 82 is formed between the piston 80and inner surface 84 of cylinder wall 86. A pair of slots 88, 90extending around the outside perimeter of the piston 80 contain a pairof pressure activated seals 92, 94. The seals 92, 94 are pre-shaped toform seal cavities 98, 100 facing upstream of the piston rod 30. It willbe understood that the seals 92, 94 and seal cavities 98, 100 may be avariety of shapes.

The seals 92, 94 are arranged so that as pressurized air 91 enters theair inlet 42, and input chamber 96 is pressurized, a seal cavities 98,100 are pressurized and the pressure activated seals 92, 94 are forcedinto engagement with the inside surface 84 of the cylinder wall 86. Inthe exemplary embodiment disclosed herein, approximately 13.8 kPa (2psi) is required to engage the seals 92, 94 with the inside surface 84.Seal 94 is intended to capture blow-by air that passes the first seal92. The small gap 82 between the cylinder wall 86 and the piston 80permits generally uniform circumferential pressurization of the seals92, 94 against the inside surface 84 around the entire circumference,thereby enhancing sealing capabilities. The pressure activated seal ofthe present pneumatic cylinder 32 is capable of maintaining a statictraction force of greater than 111 N (25 lbs.) for a period in excess of10 minutes, and preferably, a static traction force of greater than 200N (45 lbs.) for a period in excess of 20 minutes, without the need tosupply additional pressurized air.

When the pressure in input chamber 96 is released, the seals 92, 94disengage from the inside surface 84 and the piston 80 is allowed tomove freely within the cylinder 32. The pneumatic cylinder 32 mayinclude spring or other resilient compression member 102 around thepiston rod 30 to urge the piston 80 back toward the air inlet 42 whenthe compressed air 91 is released. Alternatively, a spring (not shown)may be positioned between the slide portion 24 and the track 26. Thecompression member 102 preferably has a low spring forces so as tominimize the amount of force needed for the patient to activate thecylinder.

FIGS. 6 and 7 illustrate an exemplary air pump 120 for use with thepresent portable traction device 20. The air pump 120 has a T-handle 122attached at one end by a pivot point 124. The T-handle 122 configurationoffers ergonomic advantages over a standard straight pump handle.Alternatively, a straight handle may be substituted for the T-handle. Anadjustable pressure regulator 126 may optionally be included in the pump120 or cylinder 32 (see FIG. 1) so that over-pressure situations can beprevented. The other end of the air pump 120 includes a gauge 128, whichpreferably is calibrated to read the actual amount of traction forcebeing provided to the patient, rather than pounds per square inch. Thepump, handle and gauge may be formed as a singled piece by an injectionmolding process.

A manual pressure relief mechanism 130 is also located proximate thegauge 128 for relieving the pressure in the pneumatic cylinder 32 whenthe treatment period is completed. Alternatively, the pressure reliefmechanism (not shown) may be operated by rotating the gauge 128. Airtube 40 is connected to the air pump 120 opposite the gauge 128. Avariety of pressure regulator configurations may be used in the presentinvention. For example, the pressure gauge 128 may include an internalpressure regulator.

To use the portable, cervical traction device 20, it is placed on asuitable support surface 36. The left and right knobs 70, 72 are rotatedto allow the neck of the user to fit easily between the left and rightneck supports 50, 52. The slide portion 24 is moved down on the track 26as far as possible by depressing pressure relief mechanism 130 (see FIG.7) until cylinder 32 is at atmospheric pressure.

The back of the user is placed on the support surface 36 so that theneck is cradled by the neck supports 50, 52. The neck supports 50, 52should initially contact the user in the mid cervical region, midwaybetween the tip of the earlobe and the top of the shoulder. The knobs70, 72 are turned until the neck supports 50, 52 are moved firmlyagainst both sides of the neck. The user's head is secured to the headsupport pad 76 by the support strap 77. With the head support pad 76under the shoulders, the user's head should be nearly aligned with thespine.

The user then slowly pumps air into the cylinder 32 using the air pump120. The configuration of the pump 120 permits a patient tosimultaneously view the gauge 128 and operate the pump, while inclinedin the portable traction device 20. The gauge 128 allows the user tostay within the pressure/traction force guidelines provided by thehealth care provider. The patient increases the traction force bymanually operating the pump 120 or decreases the traction force bymanually pressing the pressure relief mechanism 130. The neck supports50, 52 are properly positioned when there is solid contact at the baseof the head and the supports 50, 52 are positioned near the tip of theear lobes. When the treatment is complete, the traction force isreleased by pressing and holding the pressure relief mechanism 130 onthe air pump 120.

FIG. 8 illustrates a portable, lumbar traction device 140 in which thepneumatic cylinder 32 is attached to a portable traction device 140. Theportable, lumbar traction device 140 includes a frame 150 retaining asupport surface 152. In a first embodiment, a pelvic belt 142 retainsthe patient's pelvis to a sliding portion 154, which slides along track156. The pneumatic cylinder 32 mounted to the frame 150 is coupled tothe sliding portion 154 so that the sliding portion 154 moves along thetrack 156, creating a traction force “F” when the cylinder 32 ispressurized. A counter traction belt 148 provides a passive countertraction force on the patient's lower rib cage. The pneumatic cylinder32 preferably maintains a static traction force of greater than 445 N(100 lbs.) for a period in excess of 10 minutes, and preferably, astatic traction force of greater than 890 N (200 lbs.) for a period inexcess of 20 minutes, without the need to supply additional pressurizedair. It will be understood that two cylinders may be necessary toachieve a static traction force in excess of 445 N.

In a second embodiment, pelvic belt 142 is engaged with the pneumaticcylinder 32 by a cable 144 and pulley 146 configuration mounted at thefoot of the portable traction device 140. Counter-traction belt 148provides a passive counter traction force on the patient's lower ribcage to restrain the patient in a fixed position relative to theportable traction device 140. When the patient activates the pneumaticcylinder 32 as discussed above, the cable 144 is retracted, creating atraction force “F” on the waist belt 142 and the patient's pelvicregion. The natural. inherent friction between the sliding portion 154and the patient's pelvic region typically delivers a portion of thetraction force “F”. In either of the above embodiments, the countertraction belt 148 may also be coupled to the pneumatic cylinder 32 toprovide an active counter traction force in a direction opposite to “F”on the patient,

FIGS. 9 a–9 c illustrate an alternate embodiment of a portable, lumbartraction device 200 positioned directly on the support surface 36. Upperbody support platform 202 includes a frame 204 supporting a supportsurface 206. A moveable head rest 208 is positioned on the surface 206.Lower body support platform 210 has a support surface 214 slidablyengaged with frame 212. The surface 214 on the lower body supportplatform 210 slides in a direction “M” preferably about 0.15 metersunder the force of a pair of pneumatic cylinders 32′ (see FIG. 10). Theupper and lower body support platforms 202, 210 are connected by a hinge215 to facilitate shipping and storage of the lumbar traction device200.

An adjustable rib gripping belt 216 is attached to the upper bodysupport platform 202 to provide a passive counter traction force in adirection “C”. A pair of laterally adjustable hip gripping supports 218,220 are connected to the surface 214 so that they move in the direction“M” with the surface 214. The hip gripping supports 218, 220 areindependently adjustable and curved to generally correspond to the shapeof the user's waist, as will be discussed in connection with FIG. 11.

FIG. 10 illustrates a segment of the frame 212 of the lower body supportplatform 210. The piston rods 30′ of the pneumatic cylinders 32′ areengaged with the frame 210. Cylinder heads 31′ are attached to slidingsupport structure 222 that supports surface 214. Introduction ofpressurized air through the air inlet 42′ moves the sliding supportstructure 222 and support surface 214 in the direction “M”. Theoperation of the cylinders 32′ is substantially as discussed above inconnection with FIGS. 5–7. The pair of cylinders 32′ maintain a statictraction force of at least 890 N (200 lbs.) for a period in excess of 20minutes, without the need to supply additional pressurized air.

FIG. 11 illustrates a hip gripping device 230 for use with the portable,lumbar traction devices 20′ and 200 of the present invention. The hipgripping supports 218, 220 are shown in both the maximum and minimumlateral positions. In the exemplary embodiment illustrated in FIG. 11,the maximum and minimum lateral positions correspond to a distance of0.50 m and 0.29 m, respectively. However, it will be understood that thehip gripping device may be modified to accommodate larger and smallerusers.

The hip gripping supports 218, 220 include rigid curved members 234, 236covered with padding material 232 for the comfort of the user. Thecurves generally follow the contour of the waist of the human body.Suitable padding material include high density foam, rubber or a varietyof elastomeric materials. The rigid curved members 234, 236 include apin 238 positioned to engage with receiving slots 244 on the top of thetrack 242 and a pin 240 positioned to engage with the bottom surface 241of the track 242. To adjust the hip gripping device 230, the userrotates one or both of the hip gripping supports 218, 220 in thedirection “R” so that the pin 238 disengages from the slots 244. Whilein the rotated position, the hip gripping supports 218, 220 may be movedlaterally along the track 242 to the desired location. Rotating the hipgripping supports 218, 200 in the direction opposite to “R” will engagethe pin 230 with one of the slots 244. The hip gripping supports 218,220 may be completely disengaged from the track 242 by moving the pin240 past the ends 246 of the track 242 near the cylinders 32′ andlifting the supports 218, 220 upward. It will be understood that thewaist belt 142 of FIG. 8 may be substituted for the hip gripping device230.

To use the portable, lumbar traction device 200, it is placed on asuitable support surface 36. The hip gripping supports 218, 220 arepositioned to firmly, but comfortably, engage the waist of the user. Thesupport surface 214 of the lower body support platform 210 is movedupward toward the upper body support platform 202 as far as possible bydepressing the pressure relief mechanism 130 (see FIG. 7) untilcylinders 32′ are at atmospheric pressure.

The back of the user is placed on the support surface 206 so that thewaist is cradled by the hip gripping supports 218, 220. The hip grippingsupports should initially contact the user midway between the bottom ofthe rib cage and the top of the pelvis. The user's chest is secured tothe support surface 206 of the upper body support platform 202 by therib gripping belt 216. The head rest 208 should be placed under theuser's head. The user then slowly pumps air into the cylinders 32′ usingthe air pump 120, as discussed in connection with the portable, cervicaltraction device 20. The hip gripping supports 218, 220 are properlypositioned when there is solid contact with the top of the pelvis.

The present invention has now been described with reference to theseveral embodiments thereof. It will be apparent to those skilled in theart that many changes can be made in the embodiments described withoutdeparting from the scope of the invention. Thus, the scope of thepresent invention should not be limited to the structures describedherein, but only by structures described by the language of the claimsand the equivalents of those structures. For example, the presentportable traction device may be arranged in a variety of configurationsto facilitate traction to any part of the body.

1. A low-cost, light weight portable lumbar traction device for home useby a patient comprising: a support structure having a longitudinal axis;a carriage slidable along a portion of the support structure parallel tothe longitudinal axis, the carriage including a restraining mechanismadapted to releasably restrain a portion of a patient's body to thecarriage; a pneumatic traction force generating apparatus comprising atleast one pneumatic chamber and at least one air inlet, the pneumatictraction force generating apparatus operatively coupled to both thecarriage and the support structure to move the carriage relative to thesupport structure when the at least one pneumatic chamber is in apressurized state, the pneumatic traction force generating apparatusadapted to maintain a generally static traction force for a period inexcess of 10 minutes when in the pressurized state without additionalpressurized air being supplied; a hand pump operated by the patientfluidly connected to the at least one pneumatic chamber for injectingpressurized air into the at least one pneumatic chamber, the hand pumpbeing capable of injecting at least 138 kPa (20 psi) of pressure intothe pneumatic chamber; and a pressure relief mechanism operated by thepatient adapted to release pressure from the at least one pneumaticchamber.
 2. The apparatus of claim 1 wherein the restraining mechanismcomprises a waist belt adapted to releasably restrain a portion of thepatient's lower body to the carriage and a restraining belt adapted torestrain a portion of the patient's upper body to the support structure.3. The apparatus of claim 1 wherein the restraining mechanism comprisesa pair of opposing, laterally adjustable hip gripping supports contouredand arranged to engage with the superior edge of the patient's pelvis asthe carriage slides along the support structure.
 4. The apparatus ofclaim 1 wherein the carriage comprises a support surface to receive aportion of the patient's lower body and a counter traction restraint torestrain a portion of the patient's upper body to the support structure,the carriage sliding in a direction away from the counter tractionrestraint when pressurized air is introduced into the at least onepneumatic chamber.
 5. The apparatus of claim 1 wherein the at least onepneumatic chamber is capable of maintaining a generally static tractionforce of greater than 111 N (25 pounds) for a period in excess of 10minutes without additional pressurized air being injected into the atleast one pneumatic chamber.
 6. The apparatus of claim 1 wherein the atleast one pneumatic chamber is capable of maintaining a generally statictraction force of greater than 200 N (45 pounds) for a period in excessof 20 minutes without additional pressurized air being injected into theat least one pneumatic chamber.
 7. The apparatus of claim 1 wherein theat least one pneumatic chamber is capable of maintaining a generallystatic traction force of greater than 445 N (100 pounds) for a period inexcess of 10 minutes without additional pressurized air being injectedinto the at least one pneumatic chamber.
 8. The apparatus of claim 1wherein the at least one pneumatic chamber is capable of maintaining agenerally static traction force of greater than 890 N (200 pounds) for aperiod in excess of 20 minutes without additional pressurized air beinginjected into the at least one pneumatic chamber.
 9. The apparatus ofclaim 1 comprising a gauge indicating traction force.
 10. The apparatusof claim 1 comprising at least one pressure regulator adapted to preventthe pressure in the at least one pneumatic chamber from exceeding apredetermined value.
 11. The apparatus of claim 1 wherein the pressurerelief mechanism is incorporated in the hand pump.
 12. The apparatus ofclaim 1 wherein the pneumatic traction force generating apparatuscomprises at least one pneumatic cylinder.
 13. The apparatus of claim 1wherein the pneumatic traction force generating apparatus comprises atleast one pneumatic cylinder and at least one pressure activated seal inthe pneumatic cylinder extending circumferentially around a piston, thepressure activated seal movable between a relaxed position and anextended position so the pressure activated seal engages an internalsurface on the pneumatic cylinder when the pneumatic cylinder is in thepressurized state.
 14. A low-cost, light weight portable lumbar tractiondevice for home use by a patient comprising: an upper body supportplatform having an upper body support surface; a lower body supportplatform having a lower body support surface; a restraining mechanismadapted to releasably restrain a portion of a patient's body to at leastone of the upper or lower body support platforms; at least one pneumatictraction force generating apparatus comprising at least one pneumaticchamber and at least one air inlet, the traction force generatingapparatus operatively coupled to at least one of the upper or lower bodysupport platforms to displace at least one of the upper and lower bodysupport platforms relative to the other along a longitudinal axis, theat least one pneumatic traction force generating apparatus maintaining agenerally static traction force for a period in excess of 10 minuteswhen in the pressurized state without additional pressurized air beingsupplied; a hand pump operated by the patient fluidly connected to theat least one pneumatic traction force generating apparatus for injectingpressurized air into the at least one pneumatic traction forcegenerating apparatus, the hand pump being capable of injecting at least138 kPa (20 psi) of pressure into the at least one pneumatic tractionforce generating apparatus; and a pressure relief mechanism operated bythe patient adapted to release pressure from the at least one pneumaticchamber.
 15. The apparatus of claim 14 comprising a hinge connecting theupper body support platform to the lower body support platform.
 16. Theapparatus of claim 14 wherein the restraining mechanism comprises awaist belt adapted to releasably restrain a portion of the patient'slower body to the lower body support platform and a restraining beltadapted to restrain a portion of the patient's upper body to the upperbody support platform.
 17. The apparatus of claim 14 wherein therestraining mechanism comprises a pair of opposing, laterally adjustablehip gripping supports contoured and arranged to engage with a superioredge of the patient's pelvis as the lower body support platform slidesalong the support structure.
 18. The apparatus of claim 14 wherein atleast a portion of the restraining mechanism comprises friction betweenat least one of the body support surfaces and a portion of the patient.19. The apparatus of claim 14 wherein the at least one pneumatictraction force generating apparatus is capable of maintaining agenerally static traction force of greater than 111 N (25 pounds) for aperiod in excess of 10 minutes without additional pressurized air beinginjected into the at least one pneumatic traction force generatingapparatus.
 20. The apparatus of claim 14 wherein the at least onepneumatic traction force generating apparatus is capable of maintaininga generally static traction force of greater than 200 N (45 pounds) fora period in excess of 20 minutes without additional pressurized airbeing injected into the at least one pneumatic traction force generatingapparatus.
 21. The apparatus of claim 14 wherein the at least onepneumatic traction force generating apparatus is capable of maintaininga generally static traction force of greater than 445 N (100 pounds) fora period in excess of 10 minutes without additional pressurized airbeing injected into the at least one pneumatic traction force generatingapparatus.
 22. The apparatus of claim 14 wherein the at least onepneumatic traction force generating apparatus is capable of maintaininga generally static traction force of greater than 890 N (200 pounds) fora period in excess of 20 minutes without additional pressurized airbeing injected into the at least one pneumatic traction force generatingapparatus.
 23. The apparatus of claim 14 comprising a gauge indicatingtraction force.
 24. The apparatus of claim 14 comprising at least onepressure regulator adapted to prevent the pressure in the at least onepneumatic traction force generating apparatus from exceeding apredetermined value.
 25. The apparatus of claim 14 wherein the userpressure relief mechanism is incorporated in the hand pump.
 26. Theapparatus of claim 14 comprising a hinge connecting the upper bodysupport platform to the lower body support platform to facilitateshipping and storage of the portable lumbar traction device.
 27. Theapparatus of claim 14 wherein the upper and lower body support platformsare adapted to be positioned on a floor.
 28. The apparatus of claim 14wherein the pneumatic traction force generating apparatus comprises atleast one pneumatic cylinder.
 29. The apparatus of claim 14 wherein thepneumatic traction force generating apparatus comprises at least onepneumatic cylinder and at least one pressure activated seal in thepneumatic cylinder extending circumferentially around a piston, thepressure activated seal
 30. A low-cost, light weight portable lumbartraction device for home use by a patient comprising: a supportstructure having a track; a carriage slidable along a portion of thetrack; a restraining mechanism adapted to releasably restrain a portionof a patient's body to the carriage; at least one pneumatic cylinderoperatively coupled to the carriage and the support structure to movethe carriage along the track relative to the support structure when in apressurized state, the at least one pneumatic cylinder maintaining agenerally static traction force during a treatment period when in thepressurized state without additional pressurized air being supplied; ahand pump operated by the patient fluidly connected to the at least onepneumatic cylinder and adapted to inject pressurized air into the atleast one pneumatic cylinder; and a pressure relief mechanism operatedby the patient adapted to release pressure from the at least onepneumatic cylinder.
 31. The apparatus of claim 30 wherein the pumpfurther includes a gauge indicating traction force.
 32. The apparatus ofclaim 30 wherein the pneumatic cylinder includes at least one pressureregulator to prevent the pressure in the at least one pneumatic cylinderfrom exceeding a predetermined value.
 33. The apparatus of claim 30wherein the pump includes a pressure relief mechanism to manuallyrelease pressure in the at least one pneumatic cylinder.
 34. Theapparatus of claim 30 wherein the pneumatic cylinder comprises at leastone pressure activated seal extending circumferentially around a piston,the pressure activated seal movable between a relaxed position and anextended position so the pressure activated seal engages an internalsurface on the pneumatic cylinder when the pneumatic cylinder is in thepressurized state.
 35. A low-cost, light weight portable lumbar tractiondevice for home use by a patient comprising: an upper body supportplatform having an upper body support surface; a lower body supportplatform having a lower body support surface; a restraining mechanismadapted to releasably restrain a portion of a patient's body to at leastone of the upper or lower body support platforms; at least one pneumaticcylinder adapted to displace at least one of the upper and lower bodysupport platforms relative to the other along a longitudinal axis, theat least one pneumatic cylinder maintaining a generally static tractionforce during a treatment period when in the pressurized state withoutadditional pressurized air being supplied; a hand pump operated by thepatient fluidly connected to the at least one pneumatic cylinder forinjecting pressurized air into the at least one pneumatic cylinder, thehand pump being capable of injecting at least 138 kPa (20 psi) ofpressure into the at least one pneumatic cylinder; and a pressure reliefmechanism operated by the patient adapted to release pressure from theat least one pneumatic cylinder.
 36. The apparatus of claim 35comprising a hinge connecting the upper body support platform to thelower body support platform.
 37. The apparatus of claim 35 wherein therestraining mechanism comprises a waist belt adapted to releasablyrestrain a portion of the patient's lower body to the lower body supportplatform and a restraining belt adapted to restrain a portion of thepatient's upper body to the upper body support platform.
 38. Theapparatus of claim 35 wherein the restraining mechanism comprises a pairof opposing, laterally adjustable hip gripping supports contoured andarranged to engage with a superior edge of the patient's pelvis as thelower body support platform slides along the support structure.
 39. Theapparatus of claim 35 wherein at least a portion of the restrainingmechanism comprises friction between at least one of the body supportsurfaces and a portion of the patient.
 40. The apparatus of claim 35wherein the at least one pneumatic cylinder is capable of maintaining agenerally static traction force of greater than 111 N (25 pounds) for aperiod in excess of 10 minutes without additional pressurized air beinginjected into the at least one pneumatic cylinder.
 41. The apparatus ofclaim 35 wherein the at least one pneumatic cylinder is capable ofmaintaining a generally static traction force of greater than 200 N (45pounds) for a period in excess of 20 minutes without additionalpressurized air being injected into the at least one pneumatic cylinder.42. The apparatus of claim 35 wherein the at least one pneumaticcylinder is capable of maintaining a generally static traction force ofgreater than 445 N (100 pounds) for a period in excess of 10 minuteswithout additional pressurized air being injected into the at least onepneumatic cylinder.
 43. The apparatus of claim 35 wherein the at leastone pneumatic cylinder is capable of maintaining a generally statictraction force of greater than 890 N (200 pounds) for a period in excessof 20 minutes without additional pressurized air being injected into theat least one pneumatic cylinder.
 44. The apparatus of claim 35comprising a gauge indicating traction force.
 45. The apparatus of claim35 comprising at least one pressure regulator adapted to prevent thepressure in the at least one pneumatic cylinder from exceeding apredetermined value.
 46. The apparatus of claim 35 wherein the pressurerelief mechanism is incorporated in the hand pump.
 47. The apparatus ofclaim 35 comprising a hinge connecting the upper body support platformto the lower body support platform to facilitate shipping and storage ofthe portable lumbar traction device.
 48. The apparatus of claim 35wherein the upper and lower body support platforms are adapted to bepositioned on a floor.
 49. The apparatus of claim 35 wherein thepneumatic cylinder comprises at least one pressure activated sealextending circumferentially around a piston, the pressure activated sealmovable between a relaxed position and an extended position so thepressure activated seal engages an internal surface on the pneumaticcylinder when the pneumatic cylinder is in the pressurized state.
 50. Alow-cost, light weight portable lumbar traction device for home use by apatient comprising: a support structure having a track; at least onecarriage slidable along a portion of the track; a restraining mechanismadapted to releasably restrain a portion of a patient's body to thecarriage; a pneumatic traction force generating apparatus comprising atleast one pneumatic cylinder having a first end and a moveable piston ata second end, one of the pneumatic cylinder or the piston attached to asupport structure, and the other attached to the carriage, the at leastone pneumatic cylinder adapted to move the carriage along the trackrelative to the support structure when in a pressurized state, thepneumatic traction force generating apparatus maintaining a generallystatic traction force during a treatment period when in the pressurizedstate without additional pressurized air being supplied; a hand pumpoperated by the patient fluidly connected to the at least one pneumaticcylinder and adapted to inject pressurized air into the at least onepneumatic cylinder; and a pressure relief mechanism operated by thepatient adapted to release pressure from the at least one pneumaticcylinder.
 51. The apparatus of claim 50 wherein the pressure reliefmechanism is incorporated in the hand pump.
 52. The apparatus of claim50 wherein the carriage comprises: an upper body support platform havingan upper body support surface; and a lower body support platform havinga lower body support surface.
 53. The apparatus of claim 50 wherein theat least one pneumatic cylinder is capable of maintaining a generallystatic traction force of greater than 111 N (25 pounds) for a period inexcess of 10 minutes without additional pressurized air being injectedinto the at least one pneumatic cylinder.
 54. The apparatus of claim 50wherein the at least one pneumatic cylinder is capable of maintaining agenerally static traction force of greater than 200 N (45 pounds) for aperiod in excess of 10 minutes without additional pressurized air beinginjected into the at least one pneumatic cylinder.
 55. The apparatus ofclaim 50 wherein the at least one pneumatic cylinder is capable ofmaintaining a generally static traction force of greater than 445 N (100pounds) for a period in excess of 10 minutes without additionalpressurized air being injected into the at least one pneumatic cylinder.56. The apparatus of claim 50 wherein the at least one pneumaticcylinder is capable of maintaining a generally static traction force ofgreater than 890 N (200 pounds) for a period in excess of 10 minuteswithout additional pressurized air being injected into the at least onepneumatic cylinder.
 57. The apparatus of claim 50 wherein the pneumaticcylinder comprises at least one pressure activated seal extendingcircumferentially around a piston, the pressure activated seal movablebetween a relaxed position and an extended position so the pressureactivated seal engages an internal surface on the pneumatic cylinderwhen the pneumatic cylinder is in the pressurized state.
 58. A low-cost,light weight portable traction device for home use by a patientcomprising: a support structure; a carriage generally slidable along aportion of the support structure, the carriage including a restrainingmechanism adapted to releasably restrain a portion of a patient's bodyto the carriage; at least one pneumatic traction force generatingapparatus comprising at least one pneumatic chamber and at least one airinlet, the traction force generating apparatus operatively coupled tothe carriage and the support structure to move the carriage relative tothe support structure when the at least one pneumatic traction forcegenerating apparatus is in a pressurized state, the at least onepneumatic traction force generating apparatus maintaining a generallystatic traction force for a period in excess of 10 minutes when in thepressurized state without additional air being supplied; a hand pumpoperated by the patient fluidly connected to the at least one pneumatictraction force generating apparatus for injecting air into the at leastone pneumatic traction force generating apparatus; and a user operatedpressure relief mechanism operated by the patient adapted to releasepressure from the at least one pneumatic chamber.
 59. The apparatus ofclaim 58 wherein the restraining mechanism comprises first and secondbelts, the first belt being adapted to releasably restrain a firstportion of the patient's body to the carriage and the second beltadapted to restrain second portion of the patient's body to the supportstructure.
 60. The apparatus of claim 59 wherein the first belt isadapted to releasably restrain a portion of the patient's lower body tothe carriage and the second belt is adapted to restrain a portion of thepatient's upper body to the support structure.
 61. The apparatus ofclaim 59 wherein the first belt is adapted to releasably restrain aportion of the patient's upper body to the carriage and the second beltis adapted to restrain a portion of the patient's body to the supportstructure.
 62. The apparatus of claim 58 wherein the restrainingmechanism comprises a pair of opposing, laterally adjustable grippingsupports.
 63. The apparatus of claim 62 wherein the laterally adjustablegripping supports are contoured and arranged to engage with the superioredge of the patient's pelvis as the carriage slides along the supportstructure.
 64. The apparatus of claim 58 wherein the carriage comprisesa support surface to receive a portion of the patient's lower body and acounter traction restraint to restrain a portion of the patient's upperbody to the support structure, the carriage sliding in a direction awayfrom the counter traction restraint when air is introduced into the atleast one pneumatic traction force generating apparatus.
 65. Theapparatus of claim 58 wherein the carriage comprises a support surfaceto receive a portion of the patient's upper body and a counter tractionrestraint to restrain a portion of the patient's body to the supportstructure, the carriage sliding in a direction away from the countertraction restraint when air is introduced into the at least onepneumatic traction force generating apparatus.
 66. The apparatus ofclaim 58 wherein the at least one pneumatic traction force generatingapparatus is capable of maintaining a generally static traction force ofgreater than 20 pounds for a period in excess of 10 minutes withoutadditional air being injected into the at least one pneumatic tractionforce generating apparatus.
 67. The apparatus of claim 58 wherein the atleast one pneumatic traction force generating apparatus is capable ofmaintaining a generally static traction force of greater than 111 N (25pounds) for a period in excess of 10 minutes without additional airbeing injected into the at least one pneumatic traction force generatingapparatus.
 68. The apparatus of claim 58 wherein the at least onepneumatic traction force generating apparatus-is capable of maintaininga generally static traction force of greater than 200 N (45 pounds) fora period in excess of 20 minutes without additional air being injectedinto the at least one pneumatic traction force generating apparatus. 69.The apparatus of claim 58 wherein the at least one pneumatic tractionforce generating apparatus is capable of maintaining a generally statictraction force of greater than 445 N (100 pounds) for a period in excessof 10 minutes without additional air being injected into the at leastone pneumatic traction force generating apparatus.
 70. The apparatus ofclaim 58 wherein the at least one pneumatic traction force generatingapparatus is capable of maintaining a generally static traction force ofgreater than 890 N (200 pounds) for a period in excess of 20 minuteswithout additional air being injected into the at least one pneumatictraction force generating apparatus.
 71. The apparatus of claim 58comprising a gauge indicating traction force.
 72. The apparatus of claim58 comprising at least one pressure regulator adapted to prevent thepressure in the at least one pneumatic traction force generatingapparatus from exceeding a predetermined value.
 73. The apparatus ofclaim 58 wherein the pressure release mechanism is incorporated in thehand pump.
 74. The apparatus of claim 58 wherein the pneumatic chambercomprises at least one pressure activated seal in the pneumatic cylinderextending circumferentially around a piston, the pressure activated sealmovable between a relaxed position and an extended position so thepressure activated seal engages an internal surface on the pneumaticchamber when the pneumatic chamber is in the pressurized state.
 75. Alow-cost, light weight portable lumbar traction device for home use by apatient comprising: a support structure having a longitudinal axis; acarriage slidable along a portion of the support structure parallel tothe longitudinal axis, the carriage including a restraining mechanismadapted to releasably restrain a portion of a patients body to thecarriage; at least one pneumatic traction force generating means formoving the carriage relative to the support structure when the at leastone pneumatic traction force generating means is in a pressurized state,the at least one a pneumatic traction force generating means maintaininga generally static traction force for a period in excess of 10 minuteswhen in the pressurized state without additional pressurized air beingsupplied; a hand pump operated by the patient fluidly connected to theat least one a pneumatic traction force generating means for injectingpressurized air into the at least one pneumatic traction forcegenerating means, the hand pump capable of injecting at least 138 kPa(20 psi) of pressure into the pneumatic traction force generating means;and a pressure relief mechanism overated by the patient adapted torelease pressure from the at least one pneumatic traction forcegenerating means.
 76. A low-cost, light weight portable lumbar tractiondevice for home use by a patient comprising: an upper body supportplatform having an upper body support surface; a lower body supportplatform having a lower body support surface; a restraining mechanismadapted to releasably restrain a portion of a patient's body to at leastone of the upper or lower body support platforms; at least one pneumatictraction force generating means for displacing at least one of the upperand lower body support platforms relative to the other along alongitudinal axis, the at least one pneumatic traction force generatingmeans maintaining a generally static traction force for a period inexcess of 10 minutes when in the pressurized state without additionalpressurized air being supplied; a hand pump operated by the patientfluidly connected to the at least one pneumatic traction forcegenerating means for injecting pressurized air into the at least onepneumatic traction force generating means, the hand pump being capableof injecting at least 138 kPa (20 psi) of pressure into the at least onepneumatic traction force generating means; and a pressure reliefmechanism operated by the patient adapted to release pressure from theat least one pneumatic traction force generating means.